Apple's 1980s iPad concept, built from scratch [video]
youtube.comSome amazing skills to be able to do this. CAD, Teensy, Pi, 3D printing, PCB layout, etc.
Would have been easier to use a 90's era Powerbook guts (no touch screen though). Perhaps it is now frowned upon to sacrifice vintage hardware. (I confess to having built a Mac aquarium decades ago.)